Straddle lift truck



Nov. 27, 195] R w. JACOB STRADDLE LIFT TRUCK Filed May 6, 1948 5 Sheets-Sheet 1 FIG. 2.

RAYMOND w. JACOB N W W%/MW Attorneys 1951 R. w. JACOB STRADDLE LIFT TRUCK 3 Sheeis-Sheet 2 Filed May 6, 1948 FIG. 9.

ZZZ/32g? Inventor RAYMOND W. JACOB Afiorneys Nov. 27, 1951 JACOB 2,576,345

STRADDLE LIFT TRUCK Filed May 6, 1948 Y s SheetsSheet :5

2' /2' FIG. 7.

fi a 2 r FIG. 5.

FIG. 6.

Inventor RAYMOND w. JACOB M'forneys Patented Nov. 27, @951 UNITED STATES PATENT OFFICE 7 STRADDLE LIFT TRUCK Raymond W. Jacob, Chicago, Ill. Application May s, 1948, Serial No. 25,395

1 This invention relates to a material handling device and in particular to one that is adapted for the stacking and unstacking loaded pallets.

In any material handling area whether it is a lumber yard or a Warehouse, it is. desirable to have loading machines that require as little space as possible for maneuvering. The machine of this invention achieves this result by straddling a row of material to be handled, thus making wide passageways between rows unnecessary.

The principal object of this invention is to provide a material handling machine that is adapted to load and unload material from any one of several rows of adjacent stacks, said rows having a minimum space therebetween.

Another object of this invention is to provide a loading device capable of straddling a row of material to be loaded, unloaded ortransported. Another object of this invention is to provide a machine for loading, unloading, and transporting material the lifting members of which move a distance that is a multiple of that moved by the actuating mechanism.

Reference is made to the drawings:

Figure 1 is a central, substantially vertical section showing the parts of a general embodiment of this invention in elevation.

Figure 2 shows an end view of the lift.

Figure 3 is a fragmentary view of a detail of Figure 1. I I

Figure 4 is a partial plan view of an'alternative construction of the top frame of Figure 1.

Figure 5 shows an end view of one type of lifting claw in its traveling position. .7 i

' Figure 6 shows a top view ofone type of lifting claw in its carrying position.

Figure 7 shows an outward looking inside view of the lifting claws in their traveling position:

Figure 8 shows an end View of one type of lifting claw in carrying position.

Figure 9 is a perspective view of a modified form of a loading device of this invention particularly adapted for loading small packages.

Figure 1 of the drawings shows a view of one side of the lift which comprises a longitudinal base member I on which are mounted uprights 2 adapted to receive in sliding relation vertical member 3, and these are in turn connected by top longitudinal member 4. Reel 5, suspended therefrom, is adapted to carry fiexible fiuid pressure lines 8 to the other side of the lift and to keep them taut as member 4 goes up or down. Piston I0 is mounted in a cylinder I2 that is centrally located on longitudinal member I and of lumber 'and 2Claims. (Cl. 21475) it is actuated by hydraulic pump I3, the fluid being delivered through hydraulic line I4 to the base of the cylinder. Frame I5 is secured to the top of the piston and its vertical member I6 rides in channel I1. Cross member I8 is mounted near the top of the piston and supports sheaves 2G in which chains or cables 22 ride. The inside ends of the cable or chains are attached to the lifting claws 24 and the outside ends are attached to the longitudinal bottom frame I.

Steering and power controls shown generally at mounted at the rear of longitudinal member I. These wheels can be cased in rubber tires or can be adapted to guidance by tracks.

that this mechanism is not self-motivated, the' In the event straddle a given load by cross members 30 con-b nected between vertical members 3 at front and rear. The piston on the second side is provided with hydraulic pressure by the hydraulic line 8 carried on reel 5. Upon application of pressure to the pistons; they raise framework I5 andlift ing claws 24, and due to the way in which the chains or cables 22 are connected, the latter rises twice'as far as the former. and uprights 3. remain in position until frame I5 has risen from position 32 to position 34 or until the top of the load engages cross member 30, whichever occurs first. The purpose of providing means for raising the top member 4 is to provide horizontal shielding and supporting devices on either side of the load. Horizontal frame members in this position will prevent accidental displacement of the load. Furthermore, if the load is top heavy the members 4 serve to prevent the same from topping off the top of the carrier. The ratio between the movement of the frame l5 and the lifting claws 24 can be increased to any desired multiple by the use of additional pulleys.

' Figure 4 shows an optional design in which the frame I5 does not engage the top member 4 but is permitted to pass through an opening The top members 4" 36 therein. In thi design, the top members 4 are permanently secured to the uprights 2 and upward movement of the piston is limited by its length or by the load striking the cross members 30.

The lifting claws 40 shown in Figure 9 are such as would be used in handling pallets or other laterally rigid stacks of material and are comprised of L shaped plates having sides 42 and toes 44. Each of these L shaped load" supporting; members as is shown in Figure 9 depends loosely and is supported by a chain 22. It is to be understood that the length and shape of these toes can be altered to suit the configurationof the particular material being handled. In operation, the toes it are held under an edge of ma-. terial to be lifted until they carry, enough weight to prevent them from swinging apart and" dropping the load.

Another type of lifting claw peculiarly adapted to. usewith a material handling device of. this invention when it is employed in liftinglumber or other material lacking lateral rigidity is illustrated in Figures through 8. In: order that the machine can straddle stacksof such material and. at the-same time provide a movable lateral. sup,-v port with which to 11ft. said material, aliftingclaw is provided with toes 46 which swing in a horizontal planeon hinges 50 that are attached to vertical plate 5.2. Ehus when the machine is, intransit or passing along an intermediaterowof, material, thes'tQefi. are swung parallel; tov side I. as; isshownin Figure 5 and. Figure 7. After, the machine is in position over a stack to. be. handled, the clawsare adjusted to, the proper. level, unclamped. and swung under the load into the position shown. in Figures. 6. and 8. Piston. i0. is, raised asufficient heightfor the, claws to clear. the. highest stack in the row, and, the-.machine is ready to transport the stacksto whatever. point, isdesired. In order that a firm support, be. secured, toes 46. are. madelong enough to extend more. than halfway between the sides i. and, 2.. One set of toesiscloser together. thanthe other as isshown in Figure, Gbecause otherwise there would be interference between the. toes asthey are swung inwardly inthe samehorizontal plane.

In. conclusion, I have disclosed, a. device forloading, un oading, and, transporting material that, is. easy to operate and requires a. minimum. of space, for maneuvering.

Lclaim: r

1.. A. material. handling device comprising two parallel verticalframes, wheels attached, to the. bottom of said. frames, a horizontal framework, means, for. mounting. said framework in sliding relation. with. respect to, the vertical frames, an;

hydraulic pump mounted on one of the vertical frames, a source of power for actuating said pump, a first vertical cylinder mounted on the same vertical frame as the pump, a second cylinder mounted on the opposite vertical frame, means for conducting hydraulic fluid from the pump to said first cylinder, a flexible tube for conducting hydraulic fluid from the hydraulic pump to said second cylinder, means mounted on sai thorizontalg framework for taking up the slack said flexible-tube, pistons mounted in said first and second cylinders, means for guiding said pistons, pulley systems mounted at the tops of each of. said. pistons, separate chains passing through said pulley systems, one end of each chain bein SQQllIfidztQ; its respective vertical frame, and the other end being secured to a lifting claw.

2: A material handling device comprising two parallel! vertical sides mounted on casters, a horizontal framework rigidly connected to the tops of said sides, an, hydraulic. pump,. power means for actuating said pump, hydraulic pistonsveh tically. mounted insaid. sides, cylindersfor hold?- ing said pistons, means for connecting said, cylinders to. said, hydraulic pump, pulleys mounted on. either side, of said pistons. with their plane of rotation, at. right, angles. to said sides. chains securedto said vertical sides at one, end and to lift.- ing claws, at the other, said chains passing over 3;); saidpulleys in such manner that the lifting claws large to permitthe piston and the pulleys to pass hrou h i file; of. this Patent:

UNITED; STATES. RATENTIS Number Name Date 758,493- Abbey- Apr.- 26; 1904 1,382,328 Stone June 21 1921 1,390,337 Stubbe Sept; 13-; 1921 13480.25? -Gerlinger Jan. 8, 1924 633,024 Kofford June21; 1927 2,166,479 Buddock July 18; 1939" 50, 2,178,370 Dunha'm Oct; 31, 1939 2,25%);'8 Evans Oct. 21-, I941 2,438,277 Fife et al Mar-23; 1948 25-12333 Jaffa et' all June 20; 1950 FOREIGN. PATENTS, Number Gountry Date:

81,346 Austria. Sept. 25,.1920

RAYMOND W. JACOB;

REFERENC S- CITED-Y The. following. references are of recordein the, 

